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[flagged]


Please don't take HN threads into cheap flamewars. Or any flamewars. We're trying for just the opposite here.

https://news.ycombinator.com/newsguidelines.html


Then there's the sad case of the Mars Climate Orbiter:

1999: A disaster investigation board reports that NASA’s Mars Climate Orbiter burned up in the Martian atmosphere because engineers failed to convert units from English to metric. Mars Photo Galleries: Where Will Next Mars Rover Land? Exotic New Mars Images From Orbiting Telephoto Studio Strange Places on Mars: What Do You Want to See Next? […]

https://www.wired.com/2010/11/1110mars-climate-observer-repo...


There are two types of countries: ones that use metric system, and ones that landed a Man on the moon using the metric system...

NASA uses the metric system.


The official US foot has been based on a metric measure for more than a century now though:

    The Mendenhall Order marked a decision to change the fundamental standards of length and mass of the United States from the customary standards based on those of England to metric standards.

    It was issued on April 5, 1893, by Thomas Corwin Mendenhall, superintendent of the United States Coast and Geodetic Survey, with the approval of the United States Secretary of the Treasury, John Griffin Carlisle.
At this point every US unit of measure (length, mass, volume, temp, second, etc) is defined in terms of a metric fundemental.

The US public are really just pretending that they don't use metric.

NIST and NASA don't pretend, they're metric to the core and just slap on some funny feet for the common pleb.


> The US public are really just pretending that they don't use metric.

That’s a silly thing to say when this whole thread is complaining about how Americans don’t use metric. We’re not pretending—we really don’t use it.

I myself am quite a fan of the metric system—unusually so for an American. I use it wherever I can intuit it, but that’s very hard when you’ve lived and continue to live in a culture that (despite your weird pedantic statement) doesn’t meaningfully use it outside of the sciences. Which is a shame, because I’m extremely jealous of that 1:√2 paper ratio.

Meters aren’t so bad to get used to; a meter is about a yard (0.91 m) and a kilometer is about ten football fields (1.10 km). But the major streets in my city are all a mile‐wide [super‐]block apart, so kilometers are too inconvenient to describe my routes. Liters are easy, since every American knows the size of a two‐liter soda bottle. But despite knowing the boiling/freezing points of water in both systems (212 °F/32 °F maps to 100 °C/0 °C), and keeping the thermometer in my car on Celsius for many years, I still don’t have an intuitive grasp of temperature in metric; without calculation, I can’t express the temperature outside in Celsius, nor when given a temperature in Celsius do I have more than a vague sense of how hot or cold it is. And kilograms are right out.

That’s what it’s like for someone who’s trying. Most Americans never experience metric in common measures past the 30 cm rulers they use in grade school (which always get flipped to the inch side).


> without calculation, I can’t express the temperature outside in Celsius

I think you'd get used to it rather quickly if it becomes ubiquitous in your daily life. It's probably a little bit similar to when there's a change in currency or some such - like when the EU introduced the Euro. Someone here could maybe confirm from personal experience but my German and other EU friends all mentioned that in the first few weeks it was quite the headache, "is this price expensive or not", but after a while the numbers start to stick and make sense of their own.


Other countries, that joined the eurozone later, had months of both currencies listed to help get used to. Sure, though, getting used to another currency (was) is not hard.


I'm Antipodean and grew up on metric but can do all the imperial measurements. Both the US and UK like to not use metric (or some hybrid).

Kilograms are pretty easy. 1 L of water is 1 kg. 1 pound is 0.4536 kg but it's usually easiest to just use 0.5kg for a rough estimate and that makes it 2 pound to 1 kg. If more precision is needed then a calculator is never far away.

For temperature:

-20° is dead (it's not really, but Australians tend to feel this way), I believe this temperature can be dangerous without adequate protection -10° is Australia also doesn't really get this temperature 0° is jacket temperature, and freezing water, although the freezer is usually at -3-5° (I think) 2-3° is the fridge temperature 10° is jumper temperature 20° is roughly t-shirt temperature 22-23° is a nice comfortable temperature 25° start of a heatwave in the UK and NZ, still cool for Australia. 30° is not nice temperature unless you have a pool or aircon handy. 40° is "what are you doing moving around" temperature. Find aircon or swimming pool urgently. 45-47° is "you shouldn't have gone out to the desert" temperature.

Like imperial to metric this definitely also comes out with currency conversion. Having travelled a lot, the first few weeks are definitely the hardest, then it starts to become intuitive.

The GBP to AUD is fairly easy because it's roughly 2 AUD to 1 GBP. Things like Norway/Sweden/Denmark are harder because it's 6.90, 7.50, 4.50, these tend to just be rounded to 5 and 10, which is generally close enough to not make stupid mistakes. Things like Hungarian Forint are a bit harder again 1.00 Australian Dollar = 231.49064 Hungarian Forints, But again it's just rounding to 200 and then establishing thresholds. 10 is 2000, 50 is 10000, 100 is 20000, 1000 is 200000.

And I went down a rabbithole :)


I got used to it faster than I thought I would, just setting my phone to show me metric all the time really helps.

20C is room temp. 10C is chilly. 0C is cold, anything below -20C is dangerously cold. 30C is hot. 37C is body temp, anything above 40C is dangerous, 50C is summer in Arizona hot.


> 37C is body temp,

37 is considered slight fever. 36 is more like it


Quoting Wikipedia, the normal human body temperature range is typically stated as 36.5–37.5 °C (97.7–99.5 °F)

37 is the usual round number given for the body temperature, not 36.


>37 is the usual round number given for the body temperature, not 36.

I don't know which country/region that might be, if you look at a picture of hg thermometer - 37 would be marked red (which doesn't make it precise, of course). Young children do have higher body temperature. There is even pharmacy chain 36.6, pretty much any rounding I have ever heard - 36C.

As for quotes, here is another:

Most people probably grew up being told a body’s normal temperature was 98.6 degrees Fahrenheit (or 37 degrees Celsius). That widely accepted number originated from a study done in the mid-1800s. But newer studies suggest the average person today actually runs a little cooler than that — somewhere between 97.5 F (36.4 C) and 97.9 F (36.6 C). [0]

[0]: https://health.clevelandclinic.org/body-temperature-what-is-...


> We’re not pretending—we really don’t use it.

Of course you are you simply don't realise it.

The US foot isn't based on Washington's forearm length or anything uniquely USofA - it's literally and officially defined in terms of the meter as a fundemental unit and it's been that way for more than a century.

When you get an official US foot as a reference (for precision machining) then you get a specific metric length.


I don’t think this is a great argument: every useful unit system in the physical world can be converted to equivalent units in the same dimension.

Congress could redefine the imperial system in terms of something stupid tomorrow (like a particular bald eagle’s wingspan), but it wouldn’t be correct to say that Americans are using the “bald eagle system”: they’re measuring things the same way they were the day before.


I mean even metric is somewhat defined by the world 0°C is the freezing point of fresh water 100° is the boiling point. That's somewhat arbitrary. You could as easily have used saltwater as °F does, the difference in this case is that it's divisible in 10s 100s.

The original definition of a kilogram is 1 litre of fresh water (I think they're more precise now), but it still works for common usage.

A litre is 10cm x 10cm by 10cm of water (it's metric turtles all the way down)

Finally the original definition is where we get to the base arbitrary, it was 1/10,000,000 of the equator to the north pole (it has since evolved, from the 1790s).

What's important here is the consistency and ease of use in mathmatical units with everything being in 10s and 100s.


> Of course you are you simply don't realise it.

Don’t be ridiculous. Of course I know that the customary units are formally defined in terms of metric. I also know my milk jug, like all gallon milk jugs in America, says “3.76 L” next to “1 gal” on the label. But if I ask someone—anyone—in my family or my workplace to pick up three liters of milk, they won’t have any idea what I mean. If that’s your idea of a culture that “uses” the metric system, you have a very strange definition of the word “use.”


>nor when given a temperature in Celsius do I have more than a vague sense of how hot or cold it is

As an electrical engineer don't you deal with temperature? Pretty much all datasheets are in C.

About temps - I can convert them in my head w/o much an issue (c=5/9 * (f-32); normally I need to convert F to C only), however something as reference point: F scale was designed as 0 - freezing point brine (salt water), 100F - body temperature; the thermometers were bit off, as 100F is a slight fever (37.7). Normal human body temperature is ~36C.

My point is that 100C (boiling point) is not very useful for a person using F as a reference point when/why something feels hot or cold. 50C is already too hot and causes burns.


> As an electrical engineer don't you deal with temperature?

Sure, but I’m talking about in the context of everyday life, shooting the breeze, and all that.

> My point is that 100C (boiling point) is not very useful for a person using F as a reference point when/why something feels hot or cold.

Indeed, the mnemonic I actually use in practice is “32 °F is 0 °C; 32 °C is a really hot day.” Sadly, I still have to do the math for anything in between!


Reminds me one of the (not funny) jokes form the '80, IQ not reaches the room temperature. This shizz is virtually not-translatable (20 IQ, c'mon), however it's quite representative for the unit mix-up in US fashion, e.g. weight and force being the same unit, volume for solids (cups), hip/valley in inches (instead of degrees, on a speed square).

Overall the imperial system is quite different, in non-engineering setup, and its applications are also non-intuitive for metric users - I suppose the reverse is pretty much the same.


But that’s just cosmetics. The system itself is defined in metric.

Btw a kilogram is about 2lbs. And funnily in europe we would often order “half a kilo of X” when buying groceries.


In France, we can ask for "une livre de beurre" which directly translates to "a pound of butter" which has been standardized to 500g (half a kilogram). So yay! You can use one freedom unit in France ;)


*and the ones that landed a Man on the moon using the metric system.


And crashed a probe into Mars because someone in the chain didn't use the metric system.


>Although data was stored internally in metric units, they were displayed as United States customary units.

https://en.m.wikipedia.org/wiki/Apollo_Guidance_Computer


This conversion is cognitive load for the engineers, who eventually made a mistake with the mars climate orbiter. Now NASA uses metric exclusively.


Indeed. Freedom units are objectively inferior in every way and I'm glad NASA pilots finally got on board.


I struggle to believe some space agency ever used the imperial system (or the US spinoff) for anything mission critical.


...well NASA (or its supplier) did try - the infamous Mars Orbiter crash[0]:

The primary cause of this discrepancy was that one piece of ground software supplied by Lockheed Martin produced results in a United States customary unit, contrary to its Software Interface Specification (SIS), while a second system, supplied by NASA, expected those results to be in SI units, in accordance with the SIS.

[0]: https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_...


> According to NASA, the cost of the mission was $327.6 million

It probably makes the top 10 most expensive software defects of all time.


Microsoft Windows was likely #1.


Maybe not NASA, but what about its contractors? https://www.simscale.com/blog/nasa-mars-climate-orbiter-metr...


The gauges in the Apollo modules were all in US customary for the benefit of the pilots. AFAIK the underlying systems used metric internally, though.


Sounds like you don’t know much about the history of the United States space program.


[flagged]


Nationalistic flamewar isn't allowed on HN, regardless of which country you have a problem with. We ban accounts that post like this, so please don't do it again. I also need to ask you to please stop posting in the flamewar style generally (see also https://news.ycombinator.com/item?id=37561159).

You have, unfortunately, a long history of breaking the HN guidelines quite badly, and it looks like we've been asking you to stop for a shockingly long time:

https://news.ycombinator.com/item?id=21468133 (Nov 2019)

https://news.ycombinator.com/item?id=20358144 (July 2019)

https://news.ycombinator.com/item?id=20271687 (June 2019)

https://news.ycombinator.com/item?id=20077664 (June 2019)

https://news.ycombinator.com/item?id=19887824 (May 2019)

https://news.ycombinator.com/item?id=19073957 (Feb 2019)

https://news.ycombinator.com/item?id=18742294 (Dec 2018)

https://news.ycombinator.com/item?id=18127177 (Oct 2018)

https://news.ycombinator.com/item?id=14623050 (June 2017)

https://news.ycombinator.com/item?id=11691475 (May 2016)

https://news.ycombinator.com/item?id=11576447 (April 2016)

https://news.ycombinator.com/item?id=8634617 (Nov 2014)

I'm not going to ban you right now since the last warning was already 4 years ago, but if you keep this up, we're going to have to, so if you'd please review https://news.ycombinator.com/newsguidelines.html and stick to the rules from now on, we'd be grateful. I don't want to ban you because you've also posted good comments—but ultimately, it's bad comments that determine bannage, not good ones.


I don't think that's a uniquely American trait.


[flagged]


“terrible” is inherently subjective — it differs by personal utility function.


Well I'm English so I can only really speak for us, but there's plenty of glorification of things like:

* Driving on the left

* Our spelling

* Being bad at maths

One other thing that I always think of is Asian culture's use of chopsticks. I'm sure I'll get downvoted for this but objectively a knife and fork are far superior. They use chopsticks for cultural and historical reasons, but objectively knives and forks are better. It's not too different from the Imperial system in America.


> driving on the left

> our spelling

I said objectively worse.

The first very literally isn't objectively worse, the second is at most subjectively worse.

I don't know about English people bragging about being bad at maths, I've certainly never heard of it.

As for chopsticks: they very much are better for some dishes - noodles, either "dry" or in soup, are infinitely easier to eat with chopsticks than a knife and fork. Sushi is practically impossible to eat with any utensil besides chopsticks.

For most rice-based dishes, I think the Thais have it right: a fork and spoon are superior. But that's still subjective - it's my opinion.


> The first very literally isn't objectively worse

It is - it increases the prices we pay for cars because it's different to most of the world. It also means driving in the rest of the world is slightly more mentally jarring than it would otherwise be, and a especially bad if you're driving a British car in Europe.

> the second is at most subjectively worse.

Some are debatable, but some definitely aren't - e.g. hiccough/hiccup. Those are almost always more sensible in American English.

> noodles, either "dry" or in soup, are infinitely easier to eat with chopsticks than a knife and fork

I disagree.

> a fork and spoon are superior

Yeah this is probably true.


> It is - it increases the prices we pay for cars because it's different to most of the world. It also means driving in the rest of the world is slightly more mentally jarring than it would otherwise be, and a especially bad if you're driving a British car in Europe.

That's basically the definition of what subjective means. You think it's worse, from your point of view. There's nothing intrinsically worse about RHD vs LHD.

> Some are debatable, but some definitely aren't - e.g. hiccough/hiccup.

Hiccup is not "American" spelling, unless you're suggesting there were Americans in London in the 1570s: https://www.etymonline.com/search?q=hiccup. Until you mentioned it, I'd never once seen that bizarre spelling, and I grew up in a Common wealth country with first English immigrant parents.

> I disagree.

Which is why it's subjective. That's the point I was making.

Americans get all teary eyed and puffy-chested about their lack of universal healthcare, or, as we saw here, their use of an antiquated, and ridiculous system of measurement - both objectively worse than the alternatives (having universal healthcare, and the metric system, respectively)


> That's basically the definition of what subjective means. You think it's worse, from your point of view. There's nothing intrinsically worse about RHD vs LHD.

That's not at all what subjective means. Subjective means that something is based on opinions that people can legitimately disagree about. The fact that LHD is a worse option in the real world than RHD is not subjective, even if in isolation they are not really any different.

If most of the world was LHD then LHD would be objectively better.

> Hiccup is not "American" spelling

Ok fine, how about programme/program? Metre/meter?

> Which is why it's subjective. That's the point I was making.

Again, not what subjective means. Subjective doesn't mean "people disagree about it". People disagreed on whether or not Earth was the centre of the solar system. It was never subjective.


> Subjective means that something is based on opinions that people can legitimately disagree about.

Yes, and your claim is literally your opinion. Others probably hold the same opinion but that doesn't make it objective.

> The fact that LHD is a worse option in the real world than RHD is not subjective, even if in isolation they are not really any different.

But that's just my point. It's entirely subjective. Just because you think it's worse, doesn't mean that's objectively true.

> Ok fine, how about programme/program? Metre/meter?

I really don't think you understand what the phrase "objectively worse" means at this point.

> Subjective doesn't mean "people disagree about it"

It's not about you or I disagreeing or agreeing, and if that's what you took from what I wrote, you may want to try re-reading it. I agree with you that chopsticks are not great to eat rice with. But it's still subjective.

Subjective means something (in this case an opinion being stated as a fact) is relative to the person making it, and their view of the world. Thus it is inherently not objective.


Sour grapes much?




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